Abstract Lactic acid bacteria (LAB) are traditional dairy strains which have a long history of safe use. They are a kind of food-grade microorganisms that can be used in industry to produce lots of food and drink, such as yoghourt. In the last two decades the physiology and genetics of these bacteria have been thoroughly studied. Because of their genetic accessibility and easy to handle, LAB, in addition to their traditional applications, have been extensively developed and used for the expression of heterologous genes. So they have an important foreground in agricultural, medical and many other fields. People have developed a series of food-grade gene expression systems of LAB. This article will introduce LAB, especially their model strain Lactococcus lactis and their most useful food-grade induced expression system--nisin controlled gene expression system NICE and its food-grade inducer nisin, food-grade host, expressing vectors and applications in expressing heterologous proteins of NICE.
|
